#pragma once

#include <iostream>
#include <vector>
#include <pthread.h>
#include <semaphore.h>

const int N = 5;

template<class T>
class RingQueue
{
    void P(sem_t& s)
    {
        sem_wait(&s);
    }
    void V(sem_t& s)
    {
        sem_post(&s);
    }
    void Lock(pthread_mutex_t& m)
    {
        pthread_mutex_lock(&m);
    }
    void Unlock(pthread_mutex_t& m)
    {
        pthread_mutex_unlock(&m);
    }
public:
    RingQueue(int num = N):_ring(num),_cap(num)
    {
        sem_init(&_data_sem,0,0);
        sem_init(&_space_sem,0,num);
        _c_step = _p_step = 0;
        pthread_mutex_init(&_c_mutex,nullptr);
        pthread_mutex_init(&_p_mutex,nullptr);
    }
    //生产
    void push(const T& in)
    {
        P(_space_sem);
        Lock(_p_mutex);
        _ring[_p_step++] = in;
        _p_step%=_cap;
        Unlock(_p_mutex);
        V(_data_sem);
    }
    //消费
    void pop(T* out)
    {
        P(_data_sem);
        Lock(_c_mutex);
        (*out) = _ring[_c_step++];
        _c_step%=_cap;
        Unlock(_c_mutex);
        V(_space_sem);
    }
    ~RingQueue()
    {
        sem_destroy(&_data_sem);
        sem_destroy(&_space_sem);

        pthread_mutex_destroy(&_c_mutex);
        pthread_mutex_destroy(&_p_mutex);
    }
private:
    std::vector<T> _ring;
    int _cap;            //环形队列容器大小
    sem_t _data_sem;    //消费者关心的信号量
    sem_t _space_sem;   //生产者关注的信号量
    int _c_step;        //消费位置
    int _p_step;        //生产位置

    pthread_mutex_t _c_mutex;
    pthread_mutex_t _p_mutex;
};